The present invention relates to a novel polygonal puzzle kit including a plurality of reversibly interconnectable polygonal construction elements that can be releasably assembled to form one or more toy-like, or other three-dimensional, constructions. Assembly performed from the kit may result in a three-dimensional puzzle-like toy.
In the known, commercially available prior art, there exists a toy construction kit which is available under the trade mark "POLYDRON." This kit comprises a plurality of planar, rectilinear construction elements which are manufactured from high density polyethylene by an injection moulding process. The "POLYDRON" construction elements are several millimetres thick, and are therefore substantially rigid. The kit includes generally triangular, square and pentagonal construction elements, and the sides of these elements are all of the same length. The elements can be joined releasably to one another by means of snap-together hinges which can be formed between abutting sides of contiguous elements. To this end, each side of each construction element has a recessed portion and a protrusion which can be mated, respectively, with the protrusion and recessed portion formed in the juxtaposed side of a contiguous construction element. The contiguous elements are formed with engaging lugs and hollows respectively on the protrusions and in juxtaposition with the recessed portions, which lugs and hollows are disposed on straight lines which are parallel to the respective juxtaposed sides of the construction elements. The lugs on one of the sides of two contiguous elements snap-fit into the hollows on the other side, so as to hinge releasably the two elements together.
The "POLYDRON" construction kit has the disadvantage however that the releasable hinges which can be formed between contiguous elements are fragile, in the sense that they readily become disconnected if any twisting forces are applied across the hinges. In view of the rigidity of the individual construction elements, this means that only strictly rectilinear constructions can be made using the "POLYDRON" system, and any attempt to force the elements into an arrangement whereby twisting forces are applied across the hinges, will result in the construction collapsing.
Accordingly, it is an object of the present invention to provide an improved construction kit comprising a plurality of generally rectilinear construction elements which can be used to form non-rectilinear constructions in which twisting forces may be exerted across the joints between juxtaposed elements, without the constructions falling apart as a result of such twisting forces.
In one aspect of the present invention therefore there is provided a puzzle construction kit comprising a plurality of construction elements that can be releasably assembled to form a construction, each of which construction elements is formed from a resiliently flexible sheet of plastics material and comprises a substantially rectilinear shape, which shape is provided with a releasable hinging joining structure on one side and a cooperating structure on another side, which hinging joining structure can cooperate with the cooperating structure on another of the construction elements for releasably joining the construction elements one to another, and to form a flexible hinge therebetween.
The construction elements of the present invention generally have central panels with perimetral shapes that are triangular, square, pentagonal, hexagonal, or some other regular polygonal character. In their unjoined, unassembled form, each such element nominally is substantially planar, and the elements are constructed in such a manner that hinging joinder between adjacent elements can occur generally via coplanar approaching relative motion. The sides which define portions of the perimeter in each element are equal in length. These characteristics offer an important kind of "building-block" modularity which permits just about any two elements to be brought together for assembly. From a construction point of view, it makes no difference which of each element's two faces ends up facing the same way in the assembly as either face in the other element. From a surface-decoration point of view, however, this may not always be true.
Recognized, additionally, to be a potentially useful construction element, is one in which the central panel is, effectively, a double square (elongate rectangle).
The inherent flexibility of the construction elements in accordance with the present invention means that the construction elements can be used to form constructions in which some or all of the construction elements may be distorted from their natural, planar conditions, without applying forces across the hinges between juxtaposed elements such as to cause the hinges to fall apart.
In another aspect of the present invention there is provided a three-dimensional toy construction made from a plurality of construction elements in accordance with the present invention.
In yet another aspect of the invention, the hinging joining structure may comprise a tab which is formed integrally with the shape, and is connected thereto by a plastics hinge. The cooperating structure may define a slot adapted to receive the tab. The tab and slot may be shaped such that in the fitted position, the tab is releasably retained in the slot for forming the joint between the two sides of adjacent construction elements. The use of such tab and slot joining structure, also referred to herein as inter-element connector structure, between contiguous elements means that the joints can be subjected to a certain amount of strain without falling apart. This is advantageous because it allows constructions made in accordance with the invention to be played with as toys after assembly.
In still another aspect of the invention each side of each construction element may be provided with a tab or a slot, such that in some constructions made using such elements, each side of each element may be joined to a side of a contiguous element. The resulting construction will thus have a monocoque design which lends it further robustness and "playability".
While, as will be explained, specialized construction kits may be made in accordance with this invention--for example, kits designed to produce certain specific objects--with these kits having certain specialized construction elements, the fundamental or basic non specialized construction elements have what is referred to herein as undefined connective relationships to other elements. This undefined connectivity is a modularization scheme which allows just about any two elements to be brought together and readily joined. Also, the elements have a certain amount of interchangeability.
As will be well known to persons skilled in the art, a plastics hinge is capable of being flexed many thousands of times without damage. In some embodiments, the construction elements may be formed from polypropylene. The elements may for example be die-cut from a flat sheet of polypropylene, which may be an extruded sheet. Alternatively, the elements may be injection moulded. Other materials may, of course, be used.
Usually, the construction kit in accordance with the invention will comprise largely triangular, square and pentagonal construction elements, typically a plurality of each--the fundamental elements mentioned above. These elements can be combined to form, for example, the five platonic solids. The flexibility of the polypropylene sheet material, and the plastics hinges between contiguous elements, enables a wide variety of other rectilinear and non-rectilinear constructions to be made in accordance with the invention.
The thickness of each construction element will usually be less than about 1.0 mm, preferably 0.5-1.0 mm, and typically about 0.8 mm. The sides of the triangular, square and pentagonal elements may all be of the same length. This unit length will vary from kit to kit according to the desired use of the kit, but may be 40 to 50 mm for example. A smaller side length, e.g., 20 to 25 mm, may be used for forming more intricate three-dimensional constructions in accordance with the invention.
In some embodiments, the tab-receiving slots may be provided in flanges formed integrally with and projecting from the sides of the shapes. Advantageously, the plastics hinge joining the tab to the side of one of the elements may be set back from the side of the element and joined thereto by short cut portions, the slot formed in the flange on the other element may be stood out from the side of the other element by a similar distance, and the ends of the slots may be arcuate to join the slot to the hinge. In the construction, the tab and flange will overlap their respective opposing elements on the same side of the joint. The hinge formed between the two elements permits the two elements to be hinged relative to one another, thereby to allow the formation of three-dimensional articles. Interestingly, the tab/slot/hinge joining structure proposed by the present invention allows for a situation wherein joinder of any three or more elements offers the possibility, in a final construction, for such joined elements to lie selectively either in a state of coplanarity, or, alternatively, in either one of two mirror-image, noncoplanar "cupped" conditions. These dispositional opportunities will be explained a bit more fully at a later point in this specification.
In other embodiments, each tab may be formed with two lugs which are spaced apart in the direction of the juxtaposed construction element side, and the distance between the extremities of the lugs across the tab may be slightly greater than the width of the slots, so as to form a snap-fit between each tab and slot.
One advantage of using polypropylene for making the construction elements in accordance with the present invention is that polypropylene can be surface decorated, e.g., by litho-printing which allows the production of a surface decoration of photographic quality. Any such surface decoration may be protected by an ultraviolet fixed varnish.
In yet another aspect of the present invention therefore each of the construction elements of the kit may be decorated on at least one surface in a manner appropriate for a particular assembled construction. For example, in some embodiments, the construction may be a model animal, in which case the individual elements may be decorated in a manner appropriate for the colours and pattern of the skin or coat of the animal concerned.
Each of the construction elements may be decorated on both surfaces, and in such cases, the decorations on the two surfaces will usually be different from each other, such that the elements can be used to make two "transformable" constructions; that is to say that one construction made using the elements with one surface showing can be "transformed" by disassembly and subsequent different reassembly to make the same or a different construction with the other surface showing. The ability of several kinds of groupings of joined elements to occupy, selectively, either (a) conditions of coplanarity, or (b) conditions of two different mirror-image cupped configurations contributes greatly to such a reassembly possibility.
Of course, each of the construction elements of the same shape may be decorated with identical surface decorations such that the elements of the same kind, from a "decoration" point of view, are interchangeable with each other. In yet another aspect of the invention however, each construction element may have a unique surface decoration in the kit, such that the elements have to be assembled in a predetermined arrangement. The degree of decoration difference between contiguous elements in the construction can be varied so as to make assembly in the correct fashion either easier or more difficult. In this way, the kit of the invention may constitute a three-dimensional puzzle in the manner of, say, a jigsaw.
Computer modelling may be used for designing the surface decoration to be applied to the construction elements of the kit, so as to ensure that the decoration applied to the two-dimensional construction elements, usually before they are die-cut from the extruded sheet, gives a satisfactory visual result when the construction is made in three dimensions. The design applied to the elements may include visual clues for assembly of the elements in the correct arrangement as in a conventional two-dimensional jigsaw.
In yet another aspect of the present invention, the construction kit may comprise one or more special construction elements appropriate to the construction kit concerned. These special construction elements may comprise, for example, body parts of animals, e.g heads, legs and the like, which can be fastened to the assembled "basic" elements to finish a particular desired construction.
These and other objects and advantages which are attained by the invention will become more fully apparent as the following description is read in conjunction with the accompanying drawings.